Hydraulic transmission



4 Sheets-Sheet 1 Filed June 19, 1939 W. L, SCHOENGARTH HYDRAULIC TRANSMISSION Sept. 2

sept 24, 1940 w. L. scHoENGARrl-i HYDRAULIC TRANSMISSION Filed June 19, 1939 4 Sheets-Sheet 2 Walk/LZ;

bk NM1 sept. 24, 1940.

W. L. SCHOENGARTH HYDRAULI C TRANSMI SS ION Filed June 19,v 1939.

4 sheets-sheet s Sept. 24, E940. w. x.. scHoENGARn-l HYDRAULIC TRANSMISSION Filed June 19, 1939 4 Sheets-Sheet 4 Patented sept. 24, 1940 UNITED STATES HYDE/Amc SMISSIN Walter L. Schoengarth, Ironwood, Mich.

Application June 19, 19'39, serial m1279389 1o elm-uns. (C1. isz- 757) This invention relates to'improvements in hydraulic transmission I mechanism of the gear pump type,'wherein the circulation of fluid, such as oilv or the like, maybe controlled at will to vary the speedof a driven shaft with respect to the speed of ardriving" shaft, and one of thev objects of the 'invention is to provide improved ,means whereby the 'speed' of oneshaft may be Qquickly'brought up tothe samespeed as an- 'other shaftwithout hesitation or interruption duringy the interval ofthe shift in the transmisslon. Y

further object is" to provide in a device of ,this character,Y improved means for automatical- `,lyv relieving the fluid pressure. further vobject is tol provide improved transmission of this Acharacter which will be of a comparativelysirnple construction, compact, and efrfectiv'e and eilcient in operation.

To thev attainment of these ends and the accomplishment of other new and useful objects as ,will appear, the invention consists in the features of novelty vin substantially the construction, combination and `arrangement of the several parts hereinafter more fully described and claimed and shown in the accompanying draw- -ings illustrating this invention, and in which"r Figure 1 is a longitudinal sectional view, with partsomitted,` of a transmission of this charac- ',ter, constructed in accordance with the principles of this invention. 'Figure' 2 isa detail sectional view taken on line 2 -2 Figure 1, with parts omitted.

' Figure 3 is "'a detail sectional view taken on line A35 ,3-3 Figure 'L'withV parts omitted.

" Figure 4 is a'detail sectional View taken on line 4-4 Figure 1, with partsomitted.

y vFigure 5 is a detailed sectional View taken on une .f1-5 Figure 1, with parts omitted.-

Figure 6 is a detail sectionallview taken on line 6`6 Figure 1, with parts omitted.

Figure 7 is a detail sectional view taken on line '1--1 Figure 1', with partsfomitted.

- lFigure 8 is a detail-perspective viewof the cont'rol valve.' y Y Y Figure 9 is a AView partly in elevation, partly viin sectionv and Apartly broken away, with parts omitted, and as taken on line 9-.-,9 Figure 3.

Figure 10. is a sectional view takenv on line l,50 IU--I Figure 2, and on an enlarged scale on .une lu-ln Figures 2 and 3.

.Figure 11 is a detail sectional view taken on line I I -II Figure 12. y u

v .Figure 12 is a view similar to Figure 1 showing 5,5 the, parts in a different position,

Figure 13is a detail sectional view taken 4on "line I3-I3 Figure 1.

.section I9 is rotatably supported in a bearing 2| in the casing I1, the bearing being preferably of the ball type, while the section I8 rotatablysupvports the shaft I5 by a bearing 46.

The section I8 is provided at its free end with a :tubular portion 22 and a slotv 23 is provided in the wall of the tubular portion, for a purpose to be described.

Within the section I8 vand in proximity to the@ section I9 is arranged a chamber 24 which has communication with a chamber 25 in the section I9. Secured yto the shaft l5 for rotation there- '.with in any suitable manner so that it may be inoved longitudinally of the shaft, preferably by means of. a key or spline 26 is a gear 21 and also within the chamber" 24 and meshing with the gear 21 is another gear 28 which, when the shaft l I5 is rotated, will be rotated by the gear 21 to circulate the fluid, such as oil or the like, around the gears.

Fluid is admitted into the chamber 24 from an inlet passage 29 that receives its supply from any suitable source, the passage 29 having communi- Vcation with -a chamber 30 that vencompasses the chamber 24, communication being made through f a port or opening 3l.

Fluid entering the chamberv 24 through the fopening 3| will, when thegears are being rotated, flow around the gears to a passage 32 to be discharged from the chamber through a port or passage 33, thence into an annular chamber 34, the latter having an outlet 35 which comlmunicates with a discharge passage or pipe 36 that leads back lto the source of supply (not shown).

In order to control the speed ci rotation of the gears, it is only necessary to control the discharge of the fluid from the chamber 24 and the control of the discharge will control the presv.sure created by the fluid. This control may be effected in any suitable manner but preferably by means of a valve 31 whichis preferably elongated and is rotatable on yan axis lsubstantially y parallel with the axis of the shaft I5. The valve is mounted in section I8 of the housing and is provided with a tubular portion 38 at one end which communicates with the port or passage 33, and an outlet 39 is provided in the wall of the tubular portion 38.

This outlet 39 is adapted to be brought into communication with the passage 35 and out of communication therewith by the rotation of the valve 31. The rotation `of the valve will cause the size of the outlet 39 thereof to be increased or decreased with respect to the passage 35 and the pressure of the fluid in the chamber 24 will be controlled by the speed of discharge of the fluid from the chamber 24 through the outlet 39 of the valve 31 and the passage 35.

Thus it will be seen that by rotating the Valve 31 the speed of the transmission Will be controlled.

The valve 31 is Ipreferably provided with an end thrust bearing 49 held in position by means of an adjustable `nut or member 4I.

Mounted to slide upon the section I8 of the housing is a sleeve 42 andsecured to the sleeve is a pin 43 whichprojects through a slot 44 in the section I8 of the housing 'and enters a slot or groove 45 in the valve 31 a portion of which lgroove is spiraland another portion of which is straight or parallel with the axis of the valve. When the sleeve 42 is moved upon the section I3 of .the housing in a direction lengthwise of the axis of the section, the valve 31 through the medium of the pin 43 moving in the spiral part of the slot 45 will be correspondingly rotated to vary the size of the opening 39 in the valve 31 with respect to the outlet port 35, and when the pin is moving in the straight portionof the slot, the

vvalve will not be rotated.

The section I8 is preferablymounted for rotation in a bearing 46 of the ball type.

The sleeve 42 will rotate with the. housing when the latter is rotated by reason of the pin 43 passing through the slot 44 and also through the medium of another pin 41 which extends through the slot 23 in the tubular portion 22 of the section I8.

'This pin 41 is provided for a purpose to be hereinafter described.

The sleeve 42 is adapted to be moved longitudinally of the shaft I5 so as to vary the speed of rotation of the driven shaft, preferably by means of a hand operated lever 43 which has connection with a yoke 49 that operates in an annular groove 5l] in the sleeve. This yoke 43 is supported by a rod 5I to which it is secured and which rod is slidable in bearings 52--53 in the casing I1. The rod 5l is provided with a series of notches or seats 54-55-56-51 which seats are adapted to be selectively positioned With respect to a spring pressed pin or member 58 for determining the position of the sleeve 42 as well as the valve 31.

By operating the lever 48 the spring pressed locking element 58 will yield to permit the sleeve 42 and the rod 5I to be moved and when one of the recesses or notches is in alinement with the element 58 the latter will enter the recess and yieldingly lock or hold these parts in their adjusted position.

Motion is imparted to the driven vshaft I6 from the housing I8`-I9 through the medium of the tubular portion 22 of the section I8 and to that end there is provided a member 59 -disposed with- `in the tubular portion and secured to such portion for rotation therewith `by means of a suitable anchoring or securing element 60, such as a screw or the like.

The end of the shaft I6 is in abutting relation with the proximate end of the shaft I5 preferably with a thrust bearing 6I, preferably in the form of a ball therebetween.

The proximate ends of the shafts I 5-I6 are respectively provided with grooves or channels 62-63 (see particularly Figures 6 and '7). The grooved portion 63 of the shaft I6 passes through the member 59 (see particularly Figure 7) which latter is provided with spaced projections 64 that enter the grooves 63 in the shaft.

Slidably mounted upon the grooved extremity 62 of the shaft I5 is a collar 65 which is provided with spaced projections 66 that enter the grooves 52 and this collar is adapted under predetermined conditions to be positioned so as to overlap the proximate ends of the shafts I5 and I6 to lock these shafts together, when the parts are in the position shown inFi'gure 12.

The collar 65 is moved 'longitudinally 'of the shafts upon the operation of the hand lever 48, through the medium of the sleeve 42 and the pin 41 which passes through the v'slot 23 in the tubular portion 22 of the section I8 of the housing. This pin 41 enters a peripheral groove 61 in the collar 65 and the collar maybe moved tothe position shown in Figure 12 and held inthis position when the notch 55 is in a position to receive the spring pressed'element 58.A

It will therefore be seen that when the shaft I5 is being rotated the gears 21--28 will also be rotated and this will cause the fluid to be circulated into the chamber 24 through the opening 3l, around the gears 21-28,y thence from the chamber 24 through the passage33, into the open tubular end 38 of the valve 3-1, through the outlet port 39 of the valve, through the port 35, and thence through the passage 36 `and back to the source of supply.

By actuating the hand lever 48 and by rotating the valve 31 to change the position of the port 39 with respect to the `port 35 the discharge of the fluid from the chamber 24 will be vac-\ celerated or retarded and this will control the speed of rotation of the shaft I6 with respect to the shaft I5.

When the valve 31 is movedto the Vposition shown in Figure l2 so that the port `39 is en- '15 tirely moved out of communication with the outlet opening 35 so as to prevent the discharge of the fluid through the outlet passage 36, the housing I8-I9 will be locked for rotation With vthe shaft I 5 by reason of the pressure'built up in the chamber 24.

At this same time the collar 65 will be positioned to form a mechanical lock between the shafts I5-I6, as shown in Figure 12.

In order to eliminate interruption of Vthe power exerted to drive the driven shaft I6, should the operating lever 48 be accidentally forced to a position that the notch or recess 56 Would be in a position to receive the locking element 58, at which time the flow of the iluid would cease flowing through the outlet passage or port 39 in the valve, the pressure in the chamber -24 would be built up to a high degree. In order to relieve such excess pressure there may be pro- .f

69--10--1I into' the chamber 341' izz 161,024

tion with. the chamber v34 that has communicationv with the discharge .passage 36.

will be. permitted to vflow throughthe passages andthence through the passage or pipe 36.-

. In the. operation of this mechanism, shaft l5-is rotated, the lfluid being forced between .thegearswill result in a constant-drag on'the mechanism. Y

In order `to overcome this objection, the gear 21 is adapted to be moved laterally with respect toithe gear 28 and lengthwise of theaxisoffthe shaft. I5 by reasonof the splinefconnection 26 shown clearly in Figure 1.

Tofthat end' the `hub ofthe gear21 `is reduced,

as at 12, to form a sleeve which passes through vthe chamber 25 in the section I9 of'the housing,

and this sleeve is of anl external diameter somewhat less than the diameter of the chamberw25 so as to accommodate a bearing sleeve 13 which .encompasses the sleeve 12. This sleeve 13 isiof ia -drag on the mechanism, and obviates the necessity of the use of .an additional clutch orsimilar device. .Theshifting of the gear 21 may beaccomplished by means of a lever 14 which is pivotally.

supported, as at 15, and connected to the lever are arms 16. Links 11 are respectively pivotally connected by one end, as at 18, to the arm 16 and the other ends of the links are pivotally connected, as at 19, to ayoke or collar 80 which in turn is fastened to the sleeve 12.

It will therefore be manifest that by rocking fes thelever 14 about its pivot 'I5 the arms 16 and links 11, which constitutey a toggle mechanism,

will be operat'ed to slide the sleeve 12 upon the shaft I5 and thegear 21 laterally either into or out of the chamber 24 according tothe direction of movement of the lever 14. The gear 21'is not .entirely removed from the chamber 24 and the extent Aof such removal will be controlled'bythe Vlength of the bearing 13 as-one end of the bearing will abut the end of the chamber 25.

With this construction the power may be imlocking element 58, at the same time -leaving the discharge port 39 in the valve 31v closed, locking the. shaft I5 and I6 for rotation together. When,

however, the splined sleeve 65 is drawn froml its V.locked position with respect to the driven` shaft I6, that is from the position shown in Figurev 12, on to the shaft I 5 or into the position shown in -Figure 1, the shafts I5-I6 will be freerwith re- -spect to each other and both will be' controlled by hydraulic action. f k When the sliding rod 5I is actuatedfto force locking element 58 from the notch 51 (Figure 1) and moved to the extent that the notch 56 will .bein a position to receive the spring locking elevment 58, the port 39 in thevalve 31v rotates a when the.

completedistance from opened to closed {posi- .tion,`.and whenl the parts are inthe position as shown :in Fig. 1, the lever 48,wi1l be in an intermediate position. `Atthis time, thehydraulic actionzwillbe brought up to the same speed `as the shaft I5. Should it' be desired to lock the shaft `l5--II5 ,by thecollar, `as shown in Figure 12, the lever :48;mayl-be-forcedinto lthe position shown inl Figure `I2,;that isso.V that the rod 5I- will be'moved to position thenotch 55,so as` to receive the spring locking elementv 58. At thisV time the slot 45 in the valve 31 will be soi positioned that the pin 43 will move in the straight part or-,portion of the `slot that isfparallel with the axisof the valve. Therefore the .'valve131 will not be rotated while the pin is moving in this straight portion of the slot.

.f When thespring locking element .58 is seated inthe -notch 56 of the` rod 54, the collar 65 will. be outyof` engagement with the shaft I6 and the locky Willl be Aat freedomwith respect to the hydraulic control.

Byomoving the lever 14 back `to the position shown in Figure' 1, that is, ;sothat thegear 21 will bek positionedback into the chamber 24, the gear 21-foroes `the fluid into the discharge chamber y34. The port 39A being closed, a blocking resistance will be created upon the fluid thereby causing the .housing composed of the sections I8-I9 to rotatethe driven shaft I6, the said impeller shaft being integral with theV section I8 through they medium of `themember 59.

It is thought thatthe operation of this mechanism `will be clearly understood from the foregoing, but briefly stated it is as follows: When the parts arein the position shown` in Figure 1, 'thedischarge opening 39 inthevalve 31 will be in register with the discharge outlet 35 of the chamber 34 and the driven shaft I6 will be locked yto the housing I3-I9 through the medium of the member 59. VThe rotation of the shaft I5 rotates thel gear 21 andfthis in turn rotates the gear 28 causing ,the fluid which` flows into the chamber r24 to be circulated about'the gears, thence through the passage 33 through the valve 31 through the outlet port 39 andvthence through the discharge chamber34 out of thepassage 36.

By shifting the vlever 48 to move the sleeve 42 uponA the section I 8,;the valve 31 will be correspondingly rotated and this will vary the size of theoutlet port 39 of the valveA :with'respect' tothe outlet port 35 of the chamber 34, with the ,result that thespeed of operation ,of the shaft I6 with respect to the shaft I5 will be correspondingly varied. However, when the outlet port 3,9 of the valve 31 is entirely closed, pressure Will be built upy in the chamber 24 and this will Aloclr the. housingY I8-I9for rotation with the shaft I5.

The housing iii-'I9 vis adapted to be main- Ytained'against rotation by moving the port 39 inthe Valve 31 into register with the port 35, as

-shownin Figure 1. lThis* allows'liquid -to' flow throughthe passage 29,'chamber 30 and opening.3I,through and around the gears 21-28,

4thence to chamber 24, to the ports 39, 35 and `tion shown in Figure 12. This is turn allows the liquid to be churned in the chamber from lvwhich the gear21 has been drawn. Thiswill stop vel() vthe .flow of liquid which will in turn relieve yall drag on the housings .l8-l9 and the shaft LIS.

The sleeve B will also serve as an additional vmeans for mechanically locking the shafts I5-I6 together. When the pressure in the chamber 24 becomes excessive the relief valve 68 will yield :to allow the fluid to escape through the passages '1U-1I into the discharge or outlet chamber 34.

While the preferred form of the invention has been herein shown and described, it is to be understood that various chang-es may be made in the details of construction and in the combination and arrangement of the several parts, within the scope of the claims, without departing from the spirit of this invention.

What is claimed as new is:

l. In an hydraulic transmission, a driving shaft, a driven shaft in alinement therewith, a housing encompassing and rotatably supported independenthT of the driving shaft, a chamber in the housing, a pair of meshing pinions arranged for operation .within the chamber, one of said pinions being secured to the-driving shaft, said chamber having a liquid inlet opening and a liquid discharge outlet opening, a connection between .said housing and said driven shaft, a second casing in the housing and into which the ends of the driving and driven shafts extend, a sleeve within the last said chamber and slidable upon the proximate ends of said shafts and spanning the extremities of the shaftsv for mechanically locking the shafts together, valve mechanism for controlling the discharge of the liquid from said chamber, whereby the speed of rotationof said housing with respect to the speed of rotation of the driving shaft may be varied,

.and means for actuating at will the said valve.

2. In an hydraulic transmission, a drivingshaft, a driven shaft in alinement therewith, a housing encompassing and rotatably supported independently of the driving shaft, a chamber in the housing, a pair of meshing pinions arranged for operation within the chamber, one of said pinions being secured to the driving shaft, said chamber having a liquid inlet opening and a liquid discharge outlet opening, a connection between said housing and said driven shaft, valve mechanism for controlling the discharge of the liquid from said chamber, whereby the speed of rotation of the housing with respect to the speed of rotation of the driving shaft may be varied, means for actuating at willthe said valve, a second chamber in said housing, mechanical means within said second chamber for also locking the driving and driven shafts for rotation together, and means for operating the said mechanical means.

3. In an hydraulic transmission, a driving shaft, a driven shaft in alinement therewith, a housing encompassing and rotatably supported independently of the driving shaft, a chamber in the housing, a pair of meshing pinions arranged for operation within the chamber, one of said pinions being secured to the driving shaft, said chamber having a liquid inlet opening and a liquid discharge outlet opening, a connection between said housing and said driven shaft, a rota-table valve for controlling the discharge of the liquid from said chamber, whereby the speed of rotation of said housing with respect to the speed of rotation of the driving shaft may be varied, said valve being rotatable on an axis parallel with the axis of the driving shaft, a sleeve slidably carried by said housing, a connection between the sleeve and said valve, mechanical means embodying .1a slidable element for also locking vthe driving and driven shafts together, and means .common to .the said valve and the said slidable .element means forsimultaneously shifting them.

4. In an lhydraulic transmission, a driving shaft, a driven shaft in alinement therewith, a housing encompassing and rotatably supported independently of the driving shaft, a chamber in thehousing, afpair of meshing pinions arranged for operation within the chamber, one of vsaid pinions being secured to the driving shaft, said chamber having a liquid inlet opening and a liquid discharge outlet opening, a connection between said housing and said driven shaft, a rotatable valve for controlling the discharge of the liquid from said chamber, whereby the speed of rotation of said housing with respect to the rspeed of rotation of the driving shaft may be varied, said valve being rotatable on an axis parallel withv the axis ofthe driving shaft, means `embodying a slidable sleevekfor locking the driving and driven shafts together, and yielding locking means for maintaining said valve in the different positions into which it may be rotated.

5. In an hydraulic transmission, a driving shaft, a driven shaft in alinement therewith, a housing -encompassing and rotatably supported independently of the driving shaft, a chamber in the housing, a pair of meshing pinions arranged for operation wit'hin the chamber, one of said pinions being secured to the driving shaft,

vsaid chamber having a liquid inlet opening and a liquid dscharge outlet opening, a connection between said housing and said driven shaft, valve mechanism for controlling the discharge of the liquid from said chamber, whereby the speed of rotation of said housing with respect to the speed of Lrotation ofv the driving shaft may be varied, a sleeve slidable upon one of the shafts and over the proximate ends of the shafts for locking the shafts together, and means common tothe valve andv the said sleeve for simultaneously operating them.

6. In an hydraulic transmission, a driving shaft, a driven shaft in alinement therewith, ar

housing encompassing and rotatably supported independently of the driving shaft, a chamber in Ythe housing a pair of vmeshing pinions arranged for operation within the chamber, one of said pinions being secured to the driving shaft, -said chamber having a liquid inlet openingand a liquid discharge outlet opening, a connection between said housing and said driven shaft, valve mechanism for controlling the discharge of the liquid from said chamber, Where- -by the speed of rotation of said housing with respect to thespeed of rotation of the driving shaft may be varied, lmeans for controlling said valve, means adapting one of said pinions for lateral shifting movement with respect to lthe other of said pinion, and means for thus shifting the laterallyk shiftable pinion.

'7. In an hydraulic transmission, a driving shaft, a driven shaftin alinment therewith, a

'housing encompassing and rotatably supported independently of said driven shaft, a chamber in the housing, a pair of meshing pinions arranged for rotation in said chamber, one of pin- .ions being secured t'o the driving shaft lfor rotation therewith and for lateral `shifting movement upon `and in directions lengthwise of the shaft, means for thus laterally shifting said pinion, said chamber having a fluid inlet and a fluid outlet, valve mechanismv for controlling said outlet, .whereby the speed of rotation of the driven shaft with respect to the driving shaft may be varied, and means for controlling said valve.

8. In an hydraulic transmission, a driving shaft, a driven shaft in alinement therewith, a housing encompassing and rotatably supported independently of said driven shaft, a chamber in the housing, a pair of meshing pinions arranged for rotation in said chamber, one of pinions being secured to the driving shaft for rotation therewith and for lateral shifting movement upon and in directions lengthwise of the shaft, means for thus laterally shifting said pinion, said chamber having a fluid inlet and a fluid outlet, valve mechanism for controlling said Outlet, whereby the speed of rotation of the driven shaft with -respect to the driving shaft may be varied, mechanical means for lock-ing the shafts together, and means common to the said valve and the said mechanical locking means for controlling them.

9. In an hydraulic transmission, a driving shaft, a driven shaft in alinement therewith, a housingv encompassing and rotatably supported independently of said driven shaft, a chamber in the housing, a pair of meshing pinions arranged for rotation in said chamber, one of pinions being secured to the driving shaft for rotation therewith and for lateral shifting movement upon and in directions lengthwise of the shaft, means for thus laterally shifting said pinion, said chamber having a fluid inlet and a fluid outlet, valve mechanism for controlling said outlet, whereby the speed of rotation of the driven shaft with respect to the driving shaft may be varied, means for controlling said valve, a by-pass for the liquid from said chamber, and a relief valve for controlling said by-pass, said relief valve being operable under excessive fluid pressure in said chamber.

l0. An hydraulic transmission embodying a driving and a driven shaft, a housing rotatably vsupported independently of the driving shaft, a

pair of meshing pinions arranged and operating within the housing, one of the pinions being operatively connected with the driving shaft, said chamber having a liquid inlet and a liquid discharge outlet, an operative connection between the housing and the driven shaft, valve mechanism for controlling said discharge outlet, means for actuating the valve, one of said pinions being laterally shiftable with respect to the other, and means for thus laterally shifting the laterally shiftable pinion.

WALTER L. SCHOENGARTI-I. 

